William f



(No Model.) B

W. F. DAKE;

DOUBLE REOIPROOATING SQUARE PISTON ENGINE. No 363,368; Patented May 24, 1887.

I N S- 5 baa V606 STATES \VILLIAM F. DAKE, OF GRAND HAVEN, MICHIGAN, ASSIGNOR OF T\VO'THIRDS TO HIRAM P. PRUIM AND THOMAS CAIRNS, BOTH OF SAME PLACE.

DOUBLE RECIPROCATING SQUARE-PISTON ENGINE.

SPECIFICATION forming part of Letters Patent No. 363,368, dated May 24, 1887.

Application filed December 11, 1886. Serial No. 221,341. (No model) To all whom it may concern:

Be it known that I, WILLIAM F. DAKE, a citizen of the United States, residing at the city of Grand Haven, in the county of Ottawa 5 and State of Michigan, have invented certain new and useful Improvements in Steam-Err gines, of which the following is a specification. My invention relates to that class of engines having two rectangular pistons adapted to work in a case, said pistons acting together conj ointly for the purpose of producing a revo-' lution of the main shaft, the construction being such that the pistons themselves act as valves in operating the engine, as illustrated I in the accompanying drawings, in which Figure 1 is a front elevation of an engine constructed in accordance with my invention. Fig. 2 is a sectional view on line g yof Fig. 3. Fig. 3 is a sectional view on line X X of Fig. 1. Fig. 4 is an inside view of the face-plate, the outside view of which plate is shown in Fig. 1. Fig. 5 is a perspective of the inner piston upon an enlarged scale, in order to show more fully its construction and operation.

Similar letters refer to similar parts th roughout the several views.

A A represent the surrounding case, which may be made of iron, steel, or any suitable matcrial.

B B is a rectangular piston situated within the outer case, A A, and in close contact with the upper and lower inner faces of the surrounding case, and adapted to move horizontally backward and forward within the case.

0 O is the inner piston, which has a reciprocating motion vertically within the outer piston, B B.

D D represent the face-plate.

E is the shaft of the engine, provided with the crank F, which crank F engages with the inner piston by means of the wrist-pin T, the end of which is shown in Fig. 5.

G is a packing-plate between the pistons and the back of the frame or case, which is so con structed as to be adjustable to take up any wear which may be caused by the movement of the pistons within the case, and which thereby prevents leakage of steam. A similar packing-plate may be used between the front of the case and the front of the pistons, if desired.

H is a lever which may be used for operating the four-way valve, which is one of the ways of reversing my engine. Other wellknown devices may be used for this purpose, if desired.

I is a valve operated by the lever H.

K and K are steam passage-ways connecting with the steam passage-ways M and M and conveying the steam alternately in revers- 6o ing the engine, as more fully described hereinafter. The passage-ways M and M conduct the steam to the passage-ways K and K.

The outer piston, B B, moves in the chamber N N, formed by the inclosing-case A A, while the inner piston, O 0, moves in the chamber 0 within the outer piston. I prefer to make the inner piston with two parts, as shown in Fig. 5, for convenience in arranging thesteam-passagos. The faces of the inner pis- 0 ton serve the purpose of valves.

R and R are steam-ports opening from the piston O G into the chamber N N. S and S are also ports opening from the inner piston into said chamber N N, all arranged as shown 7 in the drawings. i

' U and U are openings from the steam-passages K and K, arranged upon the front plate and so constructed as to convey the steam at proper times into the inner piston. The steam- 8o passages K and K are located upon or within the face-plate D and crosseach other, as shown in the drawings. The outer piston, B, fits within the frame, so as to form a steam-tight packing; or it may be provided with suitable packing, if desired. The valve faces of the inner piston also fit closely within the sides of the outer piston, so as to be steam-tight. Any ordinary steaimpacking may be used in connection with this piston.

c is a steam-passage through the upper face of the outer piston, and ffandff are steam-= passages connecting with the ends of the steampassages K and K and cut into the inner surfaces of the top and bottom of the case A A, each passage f f extending from the point of connection with K K far enough back to permit connection with the ports 0 and cl as the oulter piston moves back and forth horizonta 1y.

d is a steam-passage through the outer pis ton, so arrangedas to conduct the steam alter- IOO f and chamber 0 by means of the passages K and the openings U. The steam escapes through the passage-way S into the chamber N through the port a, thus forcing the outer piston, 13 B, to the left until the port 0 connects with the chamber f, taking steam from above into the piston B B, forcing the inner piston down,which', as it descends, cuts off S a and connects ports Band I). The steam now passes from 0 into the chamber N, forcing the piston B B to the right, and the port d connects with the lower passage-way, f, tale ingthe steam into the chamber 0 below the inner piston, forcing it upward, thus completing the circuit. When the valve I is in the position shown, the exhaust-pipe e is connected with the passage M, which passage connects with the chambers ff and O by means of the passage K and opening U. While the live steam is entering, as above described,

through the various passages at one side of the piston the exhaust-steam is escaping from the opposite side of the said piston through the corresponding ports connecting with these described chambers and passages. Upon reversing the engine the live steam passes through the opposite passages and chambers, and thereby causes the pistonsto travel in the opposite direction, revolving the shaft in the opposite direction.

It will be observed that by the construction of this engine there are no valves whatever, excepting the faces of the pistons, and no ee centric or other device is needed to operate the valves, the action being directly upon the pistons, and the pistons themselvs acting as valves to cutoff and let on steam'at the proper time to give the continuous motion to the engine. By this construction the engine is very compact and light and effective, and possesses 1 great power for the space occupied by it.

Having thus described my invention,what I claim to have inventcd,and desire to secure by Letters Patent, is-

1. In a double-acting square-piston engine,

the combination of an outer shell adapted to I inclose two pistons, a piston adapted to have a reciprocating motion within the shell, and an inner piston having a reciprocating motion within the outer piston, said piston moving at right angles to the motion of the outer piston,

and said pistons serving as valves, substantially as described.

2. In a double-acting reciprocating engine of the class described, the steampassages K- chambers separated from each other, and-also having ports through which the steam is con ducted into the chamber in which the outer piston moves, substantially as described.

\VILLIAM F. DAKE.

Witnesses:

Guns. T. PAGELSON, D. GALE. 

